Because police spend so much time dealing with drug-related offenses and because marijuana is the most-used illegal drug, it would seem to follow that a pretty good chunk of the inmates in the Winnebago County Jail would be in there for pot-related crimes.

So not true.

It's a bit less than 10 percent, Andrea Tack, jail superintendent for the Winnebago County Sheriff's Department, told me on Tuesday.

Just five people were in the jail on cannabis-only charges that day, she said, and 81 were there on cannabis and other charges.

The jail's average daily census last year was 953. That means that fewer than 1 percent were jailed for weed-only offenses, and 9 percent for pot and other violations.

I'm not the only one who is surprised at the percentage.

"It's a common misconception," said Dominic Iasparro, deputy chief of the Winnebago County Sheriff's Police.

"There has been a perception that we target users of marijuana," Iasparro said. "To say law enforcement targets people for small amounts, it's simply not true.

"Our focus is on dealers ... going after those involved in the sale of large amounts and the heavy drugs."

Weed smokers who are caught with a few joints often are forgiven for the crime, which is dismissed in favor of going after more serious charges or cleared to give someone with a clean record another chance.

The local percentage of those incarcerated on marijuana charges is a bit lower than in state and federal prisons, according to the most recent data available from the U.S. Department of Justice. In 2004, the agency said 12.7 percent of state inmates and 12.4 percent of federal inmates were imprisoned for marijuana offenses.

It's understandable that especially the federal rate would be higher, said Ali Nagib, assistant director of Illinois NORML, whose mission is to move public opinion to legalize the responsible use of marijuana by adults. "The feds are not dealing with simple possession," he said.

Where the rub comes in, he said, is that some of "these are people getting a decade for nonviolent crimes, in contrast to murderers."

Nagib said a "substantial portion - if not a majority - of the underground (marijuana operations) are not dealing in weapons. ... They are small operations in their homes, or people bring it in from other states."

Colorado and Washington are the only states where recreational marijuana use is legal, but 20 states allow its use for certain medical conditions.

Marijuana is the most commonly used illicit drug, according to the 2010 National Survey on Drug Use and Health. Pot was used by 77 percent of illicit drug users - those who had used the drug at some time in the 30 days before the survey - and was the only drug used by 60 percent of them.

She said she soon may ask that the Rockford City Council consider fining those caught with a small amount of marijuana rather than treating the offense as it is now, a misdemeanor. "I think the tide is turning enough to be able to speak on it," she said.

A Gallup poll in 2013 showed that for the first time, a clear majority of Americans - 58 percent - said the drug should be legalized, compared with 12 percent in 1969. Nagib of NORML said 15 of the 20 largest cities in Illinois "already have decriminalization on the books."

But Rockford Ald. Frank Beach, R-10, said he personally has a concern about the "effect of it long range. If it gets out of hand, if it will have major effects on the health of our people.

"I need to have more information, to look at the whole thing and see what it means."